Research Suggests that Warmer Oceans Are Releasing Stored Methane

Sonar image of bubbles rising from the seafloor off the Washington coast. The base of the column is 515 meters deep (about 1/3 of a mile) and the top of the plume is at 1/10 of a mile (180 meters) deep.Credit: Brendan Philip/University of Washington

There is some contention over the veracity of the feedback loops used in various climate models. In short, everyone agrees that CO2 demonstrably captures infrared radiation and will make the earth warmer when found in higher concentrations; its presence in the atmosphere alone will undeniably create some degree of warming. This warming from CO2 alone is not what climate models use to predict future temperature, because there is a massive number of other variables and feedback loops present in Earth’s systems and cycles, e.g. water vapor, cloud cover, dust, methane concentration, ocean absorption of carbon, marine life sequestration, absorption by plant life, overall albedo, NOx concentrations, sun variability, etc.

That being said, there is reason to believe that methane could far eclipse CO2 in effect of warming as hidden stores of it in both Arctic permafrost and temperate oceans become released into the atmosphere. Methane is many times more powerful than CO2 at trapping infrared heat, which means a feedback loop involving methane could be really, really bad. Even so, there’s no way to know for sure until it happens; though if massive climate change happens (almost any educated person would say it is) living on the Earth will be shitty and we won’t be able to do anything about it. AND, as disinfonauts know, there’s no persuading the Mcoo.

WASHINGTON, D.C. – Warming ocean temperatures a third of a mile below the surface, in a dark ocean in areas with little marine life, might attract scant attention. But this is precisely the depth where frozen pockets of methane ‘ice’ transition from a dormant solid to a powerful greenhouse gas.

New research suggests that subsurface warming could be causing more methane gas to bubble up off the Washington and Oregon coast.

The study shows that of 168 bubble plumes observed within the past decade, a disproportionate number were seen at a critical depth for the stability of methane hydrates. The study has been accepted for publication in Geochemistry, Geophysics, Geosystems, a journal of the American Geophysical Union.

“We see an unusually high number of bubble plumes at the depth where methane hydrate would decompose if seawater has warmed,” said lead author H. Paul Johnson, a University of Washington professor of oceanography. “So it is not likely to be just emitted from the sediments; this appears to be coming from the decomposition of methane that has been frozen for thousands of years.”

Methane has contributed to sudden swings in Earth’s climate in the past. It is unknown what role it might contribute to contemporary climate change, although recent studies have reported warming-related methane emissions in Arctic permafrost and off the Atlantic coast.

Of the 168 methane plumes in the new study, some 14 were located at the transition depth – more plumes per unit area than on surrounding parts of the Washington and Oregon seafloor.